The Astrophysical Journal Letters (Jan 2023)

The NANOGrav 15 yr Data Set: Observations and Timing of 68 Millisecond Pulsars

  • Gabriella Agazie,
  • Md Faisal Alam,
  • Akash Anumarlapudi,
  • Anne M. Archibald,
  • Zaven Arzoumanian,
  • Paul T. Baker,
  • Laura Blecha,
  • Victoria Bonidie,
  • Adam Brazier,
  • Paul R. Brook,
  • Sarah Burke-Spolaor,
  • Bence Bécsy,
  • Christopher Chapman,
  • Maria Charisi,
  • Shami Chatterjee,
  • Tyler Cohen,
  • James M. Cordes,
  • Neil J. Cornish,
  • Fronefield Crawford,
  • H. Thankful Cromartie,
  • Kathryn Crowter,
  • Megan E. DeCesar,
  • Paul B. Demorest,
  • Timothy Dolch,
  • Brendan Drachler,
  • Elizabeth C. Ferrara,
  • William Fiore,
  • Emmanuel Fonseca,
  • Gabriel E. Freedman,
  • Nate Garver-Daniels,
  • Peter A. Gentile,
  • Joseph Glaser,
  • Deborah C. Good,
  • Kayhan Gültekin,
  • Jeffrey S. Hazboun,
  • Ross J. Jennings,
  • Cody Jessup,
  • Aaron D. Johnson,
  • Megan L. Jones,
  • Andrew R. Kaiser,
  • David L. Kaplan,
  • Luke Zoltan Kelley,
  • Matthew Kerr,
  • Joey S. Key,
  • Anastasia Kuske,
  • Nima Laal,
  • Michael T. Lam,
  • William G. Lamb,
  • T. Joseph W. Lazio,
  • Natalia Lewandowska,
  • Ye Lin,
  • Tingting Liu,
  • Duncan R. Lorimer,
  • Jing Luo,
  • Ryan S. Lynch,
  • Chung-Pei Ma,
  • Dustin R. Madison,
  • Kaleb Maraccini,
  • Alexander McEwen,
  • James W. McKee,
  • Maura A. McLaughlin,
  • Natasha McMann,
  • Bradley W. Meyers,
  • Chiara M. F. Mingarelli,
  • Andrea Mitridate,
  • Cherry Ng,
  • David J. Nice,
  • Stella Koch Ocker,
  • Ken D. Olum,
  • Elisa Panciu,
  • Timothy T. Pennucci,
  • Benetge B. P. Perera,
  • Nihan S. Pol,
  • Henri A. Radovan,
  • Scott M. Ransom,
  • Paul S. Ray,
  • Joseph D. Romano,
  • Laura Salo,
  • Shashwat C. Sardesai,
  • Carl Schmiedekamp,
  • Ann Schmiedekamp,
  • Kai Schmitz,
  • Brent J. Shapiro-Albert,
  • Xavier Siemens,
  • Joseph Simon,
  • Magdalena S. Siwek,
  • Ingrid H. Stairs,
  • Daniel R. Stinebring,
  • Kevin Stovall,
  • Abhimanyu Susobhanan,
  • Joseph K. Swiggum,
  • Stephen R. Taylor,
  • Jacob E. Turner,
  • Caner Unal,
  • Michele Vallisneri,
  • Sarah J. Vigeland,
  • Haley M. Wahl,
  • Qiaohong Wang,
  • Caitlin A. Witt,
  • Olivia Young,
  • The NANOGrav Collaboration

DOI
https://doi.org/10.3847/2041-8213/acda9a
Journal volume & issue
Vol. 951, no. 1
p. L9

Abstract

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We present observations and timing analyses of 68 millisecond pulsars (MSPs) comprising the 15 yr data set of the North American Nanohertz Observatory for Gravitational Waves (NANOGrav). NANOGrav is a pulsar timing array (PTA) experiment that is sensitive to low-frequency gravitational waves (GWs). This is NANOGrav’s fifth public data release, including both “narrowband” and “wideband” time-of-arrival (TOA) measurements and corresponding pulsar timing models. We have added 21 MSPs and extended our timing baselines by 3 yr, now spanning nearly 16 yr for some of our sources. The data were collected using the Arecibo Observatory, the Green Bank Telescope, and the Very Large Array between frequencies of 327 MHz and 3 GHz, with most sources observed approximately monthly. A number of notable methodological and procedural changes were made compared to our previous data sets. These improve the overall quality of the TOA data set and are part of the transition to new pulsar timing and PTA analysis software packages. For the first time, our data products are accompanied by a full suite of software to reproduce data reduction, analysis, and results. Our timing models include a variety of newly detected astrometric and binary pulsar parameters, including several significant improvements to pulsar mass constraints. We find that the time series of 23 pulsars contain detectable levels of red noise, 10 of which are new measurements. In this data set, we find evidence for a stochastic GW background.

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